Safety and effectiveness of endoscopic endonasal intracranial aneurysm clipping: a systematic review

Once considered far-fetched, endoscopic endonasal clipping (EEC) has been reported as a feasible alternative route for treating intracranial aneurysms located in the midline. Appropriately, debates regarding EEC applicability have arisen amongst the neurosurgical community. We aim to define the safety, effectiveness, and current state-of-art in the use of EEC for intracranial aneurysms. Two databases (PubMed, Cochrane) were queried for intracranial aneurysms that underwent EEC between inception and 2019. Literature review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Data regarding clinical presentation, radiological imaging, and outcome were extracted and analyzed from selected publications. Nine studies with 27 patients (8 males, 19 females), harboring 35 aneurysms (9 ruptured, 26 nonruptured), met the predetermined inclusion criteria. Patient age range is from 34 to 70 (median = 50) years old. Four aneurysms were considered not suitable for EEC during the procedure, and two aneurysms required additional treatment, leading to an overall treatment success (obliteration) rate of 86%. Complications occurred in 7 patients (26%), including CSF leakage in 5 patients (18%) and ischemic complications in 4 (15%). Among the cases reported, complications occurred more frequently in posterior circulation aneurysms in comparison with anterior circulation aneurysms (62.5 vs 10.5%). Ischemic complications occurred in 4 out of 8 posterior circulation aneurysms. Although feasible, EEC is associated with a significant risk of complications, with rates identified that are significantly higher than established open clipping or endovascular management. The current data suggest that transcranial clipping and endovascular occlusion are still the primary indication for treating intracranial aneurysms.